Hovnatanian Crater

Today's color image features Hovnatanian crater, named for Armenian painter Hakop Hovnatanian. The crater's elliptical shape and the bright rays' butterfly pattern indicate that a very oblique impact produced Hovnatanian. The brightness of the rays indicate that they are relatively young features on Mercury's surface.

This image was acquired as a targeted high-resolution 11-color image set. Acquiring 11-color targets is a new campaign that began in March 2013 and that utilizes all of the WAC's 11 narrow-band color filters. Because of the large data volume involved, only features of special scientific interest are targeted for imaging in all 11 colors.

Date acquired: May 01, 2013
Image Mission Elapsed Time (MET): 9751363, 9751355, 9751351
Image ID: 3986986, 3986984, 3986983
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filters: 9, 7, 6 (996, 748, 433 nanometers) in red, green, and blue
Center Latitude: -7.39°
Center Longitude: 172.9° E
Resolution: 394 meters/pixel
Scale: Hovnatanian crater is about 34 km (21 miles) long.
Incidence Angle: 15.7°
Emission Angle: 40.0°
Phase Angle: 28.0°

Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Sibelius Crater

The central peaks of Sibelius crater are not actually so central, but instead are offset to the southwestern side of the crater. The smooth, flat surfaces surrounding the peaks are composed of solidified impact melt, which pooled in the crater floor and outside the rim but is concentrated to the northeast. These observations suggest that the impactor that formed Sibelius came at an oblique angle from the southwest, with central peaks offset up-range and melt splashing out of the crater down-range. The crater is still largely circular, as only the very shallowest impact angles result in oblique craters such as Hovnatanian. North is up in this image.

Date acquired: December 05, 2012
Image Mission Elapsed Time (MET): 263234346
Image ID: 3085867
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -48.83°
Center Longitude: 213.9° E
Resolution: 155 meters/pixel
Scale: Sibelius crater is 92 km (57 mi.) in diameter
Incidence Angle: 60.3°
Emission Angle: 35.9°
Phase Angle: 32.8°

Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Hovnatanian Crater

Hovnatanian crater was formed by an object that impacted at a very oblique angle, causing the crater to appear elliptical. Although impacts at most angles produce circular craters, impacts with incidence angles less than 15º (from the horizontal) will create elliptical craters. The rays of Hovnatanian form a "butterfly" pattern, which also indicates an oblique impact.

Date acquired: January 16, 2012
Image Mission Elapsed Time (MET): 235218286
Image ID: 1273501
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -7.7°
Center Longitude: 172.6° E
Resolution: 58 meters/pixel
Scale: Hovnatanian crater is approximately 33 km (21 mi.) long.
Incidence Angle: 77.3°
Emission Angle: 55.6°
Phase Angle: 132.9°

Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington